1. Field of the Invention
This invention relates to a stabilizing mechanism for a line trimmer device. More specifically, it relates to a stabilizer for trimming devices that utilize a rapidly rotating monofilament line. Hereinafter, said trimming devices are collectively referred to as "line trimmer devices" or "line trimmers."
Line trimmer devices are widely used both privately and commercially for lawn care. Generally, these devices use a rapidly rotating monofilament line to cut and remove vegetation or debris. Cutting and dispersement of the vegetation and debris is accomplished by the whipping action of a rapidly rotating line. The line first strikes the vegetation severing it at or near the point of impact and then clears the cuttings from their original position with the whipping action of the line. One commonly known commercial embodiment of such trimmers is a "WEEDEATER."
In most commercial embodiments of line trimmers, the monofilament line is deployed from within a line compartment or hub in which the line is spooled. The hub serves as a means for rotating an extension of the line that protrudes from the hub. In most cases, the hub is rotated by either an electric or gasoline motor. An operator using the trimmer controls the cutting path by way of a handle shaft with spaced handle grips.
Also, in most commercial embodiments of the line trimmers, the cutting head is located at a distal end of the extension handle shaft away from the handle grips. To perform the desired cutting, the cutting head is held and manipulated above, but proximate to the ground at a distance from the user's body. As a result of the cantilevered weight of the line trimmer devices, the user may suffer fatigue and muscle strain in a relatively short time. In addition, vibration of the motor contributes to the fatigue and muscle strain.
Another problem associated with the instability of line trimmer devices is the difficulty in obtaining a uniform cut. People spend a great deal of time and money caring for their lawn. Line trimmer devices have become one of the most important pieces of lawn care equipment because of their versatility and ability to reach places that ordinary lawnmowers cannot gain access. However, due to the vibration and unwieldiness of the line trimmer devices, ordinary people have difficulty maintaining a constant cutting height and uniform cutting path resulting in an unevenly cut lawn. Thus, there is a need for a device to stabilize and support the line trimmer device thereby minimizing fatigue and muscle strain and promoting a more uniform cut. Also, the stabilizer should provide freedom of movement in all directions.
2. Related Art
Numerous efforts have been made to design stabilizing devices for trimming devices. These efforts include U.S. Pat. No. 4,756,146 which issued to Rouse on Jul. 12, 1988. This device includes a string trimmer head with a bulbous extension on the bottom of the head. The bulbous extension is used to guide the head during use, but does not include any rolling means.
Another effort is U.S. Pat. No. 5,095,687 which issued to Andrew, et al. on Mar. 17, 1992. This device consists of a castor wheel attached to the line trimmer device handle shaft using a frame assembly and a clamp.
An additional effort is U.S. Pat. No. 4,981,012 which issued to Claborn on Jan. 1, 1991. This device uses a wheel, frame, and clamp to allow operation of the line trimmer device in a vertical plane.
A fourth prior effort is U.S. Pat. No. 4,873,819 which issued to Shivers, et al. on Oct. 17, 1989. This invention is a grass trimmer that includes a castor wheel assembly integrally attached at the head of the cutter.
Another prior effort is U.S. Pat. No. 4,845,929 which issued to Kawasaki, et al. on Jul. 11, 1989. Like Shivers, this device includes a castor wheel at the head of the cutter.
Other prior efforts include U.S. Pat. No. 4,922,694 which issued to Emoto on May 8, 1990, U.S. Pat. No. 4,829,755 which issued to Nance on May 16, 1989, and U.S. Pat. No. 5,092,112 which issued to Buckendorf, Jr. on Mar. 3, 1992. Each of these devices uses a frame and clamp to attach a two wheeled axis to a line trimmer device.
Finally, U.S. Pat. No. 2,775,857 which issued to Holmes, et al. on Jan. 1, 1957 includes a stabilizing roller attached to the handle of an oscillating blade edger.
In view of the known stabilizing devices, this invention represents an improvement for stabilizing line trimmers and provides a simple, compact, low cost design that permits truly free movement in all directions along the ground's surface. The simple wheel designs do not permit the side-to-side movements typically used in trimming with a line trimmer device. Likewise, the castor wheel designs do not readily maneuver in all directions due to the uneven lawn terrain. Finally, the bulbous extension does not provide for smooth, low-friction movement over the lawn. A modification is the use of a free rolling ball support that allows easy movement in all directions. Consequently, this modification goes beyond the teachings of the prior efforts.